Computational & Technology Resources
an online resource for computational,
engineering & technology publications
PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON ENGINEERING COMPUTATIONAL TECHNOLOGY
Edited by: M. Papadrakakis and B.H.V. Topping
Comparison and Development of Mesh Motion Using Radial Basis Functions
T.C.S. Rendall and C.B. Allen
Department of Aerospace Engineering, University of Bristol, England
T.C.S. Rendall, C.B. Allen, "Comparison and Development of Mesh Motion Using Radial Basis Functions", in M. Papadrakakis, B.H.V. Topping, (Editors), "Proceedings of the Sixth International Conference on Engineering Computational Technology", Civil-Comp Press, Stirlingshire, UK, Paper 100, 2008. doi:10.4203/ccp.89.100
Keywords: radial basis function coupling, fluid-structure interpolation, information transfer, compact functions, aeroelasticity.
A multivariate interpolation scheme, using radial basis functions, is presented for volume mesh motion. The method has several significant advantages. Primarily, all mesh structure and type dependence is removed, and all operations are performed on totally arbitrary point clouds of any form. Hence, all connectivity and user-input requirements are removed and the method may equally well be applied to structured and unstructured grids. Furthermore, no computations are required during an unsteady simulation, just matrix-vector multiplications, since the required dependence relations are computed only once prior to any simulation and then remain constant. This property means the method is both perfectly parallel, since only the data relevant to each structured block or unstructured partition is required to move those points, and totally independent from the flow-solver.
Radial basis functions offer a neat and compact way to define mesh motion, and a comparison to the more conventional Laplacian approach shows excellent agreement on both structured and unstructured meshes. Use of a greedy algorithm to reduce the number of surface points defining the mesh motion readily allows the method to be applied to large cases whilst preserving the good quality deformation even for significant shape changes. This is demonstrated by deforming an eight million cell structured multiblock mesh into the 18th mode shape of a transport aircraft wing.
purchase the full-text of this paper (price £20)